Pink Gables was a building that Iris Wildthyme owned on the Moon. It was built as a locus point to contain a disembodied intelligence that Iris had corralled on earth one night.
When Iris bought Edwin Turner to the house, she was able to command the intelligence to perform all manner of tasks throughout the house, from cooking to sweeping the chimney.
Through the intelligence, multiple disembodied humans came to inhabit the house throughout the years. As the house lay empty they exerted greater control, drawing others to the house, the most prominent being Joyce and Edward. The house was ultimately destroyed after they goaded the intelligence into lashing out upon Irises return.
Once Iris had convinced Joyce of greater things beyond Pink Gables, the humans left for the open universe. The houses remains were drawn in by the intelligence soon after and shaped into the form of a daddy long legs, leaving the moon behind. (AUDIO: Dark Side)